What I got so far is that the person who started the thread just wants to have tomb part separated from masjid. For my humble understanding, a tomb must not be confused with masjid and a masjid should not be confused with a tomb. The hadiths from books are presented in first post and they seem pretty clear on it. Now if this seems to be a problem then no one but KSA authorities have to do it or to be informed.:) Personal opinions hardy achieve anything.
I do not know if people really think the actual tomb part is really a place of worship or its a masjid, so why worry. Its just happened to be in the vicinity after expansion and people visit it while worshipping in masjid area. (correct me if i am wrong).
Authourities stop people doing uncontrolled emotional acts there anyway.
P.S. Examples such as Taj mahal, pyramids do not have any relevance since they are only tombs.